The visually evoked potential (VEP) generated by changing the luminance of a large unstructured field is a potentially useful way of assessing visual function because it can be applied to a wide variety of patients including babies and patients with opacities of the cornea, lens or vitreous. The essentially nonlinear nature of the VEP elicited in this way requires the use of a stimulus that is sufficiently general to adequately test the response characteristics. To this end we propose the use of a new stimulus, the pseudorandom binary sequence which has many of the properties of Gaussian White Noise but which is much better controlled and which can be used in a signal averaging mode. We propose to explore the use of this stimulus and to develop the appropriate output metrics such as the power spectrum and cross correlation function in normals and abnormals and to develop a protocol for efficient VEP testing that can be realized as an accessory for routine signal averaging equipment.